1. Field of the Invention
This invention relates in general to the stained glass craft industry and in particular to providing angular guides for positioning the sides of three dimensional stained glass objects.
2. Prior Art
One of the common difficulties encountered by stained glass artists and crafters is the accurate positioning of sides for three dimensional objects such as boxes, candle holders, and lampshades. In order for the finished piece to be aesthetically pleasing, it is necessary that square corners of objects actually be square and that items having more than four sides have the sides arranged in a regular pattern such that the eye cannot detect any noticeable difference between the angles formed by each pair of sides. This problem has been addressed by one manufacturer of stained glass related products.
Morton Glass Works of Morton, Ill. has marketed a device called the GS Assembly Tray which is a plastic tray with three dimensional cavities molded into the tray in such a manner that pieces of glass can be laid against adjacent sides of a cavity with such pieces located relative to each other at some desired angle. While the device attempts to resolve alignment difficulties, it has several drawbacks. The first is the requirement that a straight wire having the approximate thickness of the glass be set in the corner of the cavity formed by the two sides being used to position the glass. The purpose of this wire is to aid in the formation of a true corner joint in which only the inside edges of the glass pieces touch. If the wire is not used or is of a diameter smaller than the glass thickness, there is a good possibility that one edge will overlap the other. If beveled glass is being used for the sides, the wire serves no useful purpose since the bevels create a void area in the corner. The second drawback is that once the sides are positioned, it is not possible to view both sides of the seam so there is some uncertainty as to whether or not the sides have been positioned properly before tack soldering. The third drawback is that when the sides and base of a box are properly positioned in the device, only the insides of the seams are visible and available for tack soldering. Additionally the manufacturer's recommendation is that only the inside corner formed by the three sides be soldered. This is often awkward because the portion of the inside of the joint capable of accepting solder is quite small and the sides and base interfere with the relatively fat soldering iron. The fourth drawback is that the cavities are sized to handle relatively small pieces of glass. If the glass piece being used extends too far beyond the top edge of the cavity, gravity will cause it to pivot about this edge of the cavity and either fall or skew out of position unless one hand is used to support the pieces leaving only one hand free to tack solder. The fifth drawback is that the manufacturer specifically limits the user to performing modest tack soldering since the tray cannot withstand the heat of soldering a seam. Inadvertent contact with a hot soldering iron will also melt the tray at the point of contact.
The most common method taught students for forming the square corners of a box follows. Position and fix two straight edged pieces at a ninety degree angle or actually position and fix a carpenter's square on a work surface. Using the corner thus formed, position two pieces of glass against each edge and hold them together in such a manner that the corners of the glass touch. While holding the pieces together with one hand, tack solder the top of the corners together and check the alignment. If it is not acceptable, melt the tack with a soldering iron, reposition, and tack until it is. Then run small tacks along the seam. Rotate the assembly ninety degrees and add a side repeating the process for aligning and tacking until all four sides are tacked together. This method, while common, has the drawback that while the bottom edges of the glass may be positioned at ninety degrees in a horizontal plane, it is very difficult to assure that the sides, as they are tacked in position, lie in a vertical plane. If, as is also quite common, one of the pieces of glass is not cut square with the bottom edge, the attempt to align the edges of the glass can actually force one or both sides out of a vertical plane. Thus it becomes more difficult to align subsequent sides. The alignment problem is exacerbated since it frequently takes two hands to put the pieces in proper alignment. The crafter must then hold them in position with one hand while tack soldering with the other.
When making boxes with more than four sides, the most common practice is to lay out the angle between two sides on a work surface, affix two straightedges to the worksurface along the lines, and repeat the process noted above for the rectangular box. The alignment difficulties associated with making a square cornered object are increased since there are more opportunities for vertical misalignment. Once again the problem of needing both hands to obtain the proper alignment and then trying to hold that alignment with one hand while tack soldering with the other arises.
Perhaps the most difficult alignment problem of all stained glass projects is making a lampshade comprised of some number of individual panels whose sides are tapered to form the flare of the lampshade. The alignment problems associated with a box are now compounded because the panels do not lie in a vertical plane and are actually to be inclined to the horizontal at some unknown angle. The most common technique taught to align the sides into a nominal conical shape is quite complicated. The first step is to lay out the panels on a flat surface with their tapered sides touching and forming an arc. Next the panels are separated a small amount from each other with the edges of adjacent sides remaining parallel. The sides are then taped into this position by running some kind of adhesive tape from side to side until all sides are held in their relative positions. The next step is to pick up the sides starting at the center of the smallest arc until all the sides are resting on their bottom edges. After pulling the two end sides into a position in which their edges touch, they too are taped together. The sides are then carefully arranged into a regular pattern to determine if too much or too little gap was left between the sides before the tape was applied. The gap is required because when the sides are moved from a horizontal plane to the plane of the cone, the inside edges of the glass will become closer together. If the inside edges are now too far apart, the process will have to be repeated with a smaller gap. The next step is to turn the assembly upside down and set it into some circular shaped device such as a bowl or a can whose opening approximates the diameter of the middle of the cone. This allows the glass pieces to rest against the restraining diameter while the tape prevents them from rotating about the support point. The lampshade is now somewhat stable and the inside seams may be tack soldered. However, it is possible that the heat of the tack soldering can burn the tape on the outside of the lamp particularly any tape below the rim of the support device since it cannot be seen if the inside corner edges actually touch. Once the lampshade has been soldered sufficiently to gain some strength, it may be removed carefully from the bowl or can and finish soldered. Care must still be exercised because the tack soldering may not prevent the nominal circular cross section from deforming into an oval. Making a stained glass panel lamp-shade is a difficult process with many different parameters to control such as setting the gap between the sides properly, taping the sides securely enough so that the tape will support the glass but won't remove the copper foil burnished to the edges of each piece when the tape is removed, and assuring that the sides remain uniformly positioned during soldering so the lamp retains a "circular" cross section.
No device is known that can positively position the sides of stained glass boxes at the proper horizontal angle while assuring that they remain in a vertical plane and further can hold the sides in this position while being tack soldered. Additionally, no device is known that can positively position the sides of a stained glass panel lampshade easily and correctly and hold the sides in this position.